301 research outputs found

    Ionized and hot molecular outflows in the inner 500 pc of NGC1275

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    The role of feedback from Active Galactic Nuclei (AGN) in the evolution of galaxies is still not not fully understood, mostly due to the lack of observational constraints in the multi-phase gas kinematics on the ten to hundred parsec scales. We have used the Gemini Near-infrared Integral Field Spectrograph (NIFS) to map the molecular and ionized gas kinematics in the inner 900×\times900 pc2^2 of the Seyfert galaxy NGC1275 at a spatial resolution of ∼\sim70 pc. From the fitting of the CO absorption bandheads in the K-band, we derive a stellar velocity dispersion of 265±26265\pm26 km s−1^{-1}, which implies a black hole mass of MSMBH=1.1−0.5+0.9×109M_{\rm SMBH}=1.1^{+0.9}_{-0.5}\times10^9 M⊙_\odot. We find hot (T≳1000T\gtrsim1000 K) molecular and ionized outflows with velocities of up to 2 000 km s−1^{-1} and mass outflow rates of 2.7×10−2M⊙2.7\times10^{-2} {\rm M_\odot} yr−1^{-1} and 1.6M⊙1.6 {\rm M_\odot} yr−1^{-1}, respectively, in each of these gas phases. The kinetic power of the ionized outflows corresponds to only 0.05 per cent of the luminosity of the AGN of NGC 1275, indicating that they are not powerful enough to provide significant AGN feedback, but may be effective in redistributing the gas in the central region of the galaxy. The AGN driven outflows seem to be responsible for the shocks necessary to produce the observed H2_2 and [Fe II] line emission.Comment: Accepted for publication in MNRA

    Designing Behavioral Interventions That Work: The Triple T – Triple R Competing Pathways Model

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    Increasing numbers of children are entering our nation’s schools with mental or behavioral health problems. Although many of these children are included in general education programs, teachers report feeling under- or unprepared to manage problematic behaviors. This is not surprising given that reviews of teacher training programs have evidenced limited coursework in classroom management. Within this paper, we present a framework, the Triple T – Triple R Competing Pathways Model, that is grounded in the tenets of Applied Behavior Analysis (ABA). ABA has decades of empirical evidence to support its use in the classroom. Triple T – Triple R simplifies the competing pathways chart frequently utilized within ABA, rendering our model accessible to teachers who might not have previous training or experience with application of behavioral tenets

    Morphology of AGN Emission Line Regions in SDSS-IV MaNGA Survey

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    Extended narrow-line regions (NLRs) around active galactic nuclei (AGN) are shaped by the distribution of gas in the host galaxy and by the geometry of the circumnuclear obscuration, and thus they can be used to test the AGN unification model. In this work, we quantify the morphologies of the narrow-line regions in 308 nearby AGNs (z=0−0.14z=0-0.14, \lbol ∼1042.4−44.1\sim 10^{42.4-44.1} \erg{}) from the MaNGA survey. Based on the narrow-line region maps, we find that a large fraction (81\%) of these AGN have bi-conical NLR morphology. The distribution of their measured opening angles suggests that the intrinsic opening angles of the ionization cones has a mean value of 85--98∘^\circ with a finite spread of 39-44∘^\circ (1-σ\sigma). Our inferred opening angle distribution implies a number ratio of type I to type II AGN of 1:1.6--2.3, consistent with other measurements of the type I / type II ratio at low AGN luminosities. Combining these measurements with the WISE photometry data, we find that redder mid-IR color (lower effective temperature of dust) corresponds to stronger and narrower photo-ionized bicones. This relation is in agreement with the unification model that suggests that the bi-conical narrow-line regions are shaped by a toroidal dusty structure within a few pc from the AGN. Furthermore, we find a significant alignment between the minor axis of host galaxy disks and AGN ionization cones. Together, these findings suggest that obscuration on both circumnuclear (∼\sim pc) and galactic (∼\sim kpc) scales are important in shaping and orienting the AGN narrow-line regions.Comment: 14 pages, 7 figures, and 1 table, accepted for publication in MNRA

    Optical and mid-infrared neon abundance determinations in star-forming regions

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    We employed observational spectroscopic data of star-forming regions compiled from the literature and photoionization models to analyse the neon ionic abundances obtained using both optical and mid-infrared emission-lines. Comparing Ne++/H+ ionic abundances from distinct methods, we found that, in average, the abundances obtained via IR emission-lines are higher than those obtained via optical lines by a factor of 4. Photoionization models with abundance variations along the radius of the hypothetical nebula provide a possible explanation for a large part of the difference between ionic abundances via optical and infrared emission-lines. Ionization Correction Factor (ICF) for the neon is obtained from direct determinations of ionic fractions using infrared emission-lines. A constant Ne/O ratio (logNe/O \approx -0.70) for a large range of metallicity, independently of the ICF used to compute the neon total abundance is derived.Comment: 17 pages, 14 figures, accepted by MNRA

    Circumnuclear star formation in Mrk 42 mapped with Gemini Near-infrared Integral Field Spectrograph

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    We present Gemini Near-infrared Integral Field Spectrograph (NIFS) observations of the inner 1.5×1.51.5\times1.5 kpc2^2 of the narrow-line Seyfert 1 galaxy Mrk 42 at a spatial resolution of 60 pc and spectral resolution of 40 km s−1^{-1}. The emission-line flux and equivalent width maps clearly show a ring of circumnuclear star formation regions (CNSFRs) surrounding the nucleus with radius of ∼\sim500 pc. The spectra of some of these regions show molecular absorption features which are probably of CN, TiO or VO, indicating the presence of massive evolved stars in the thermally pulsing asymptotic giant branch (TP-AGB) phase. The gas kinematics of the ring is dominated by rotation in the plane of the galaxy, following the large scale disk geometry, while at the nucleus an additional outflowing component is detected blueshifted by 300-500 kms−1^{-1}, relative to the systemic velocity of the galaxy. Based on the equivalent width of Brγ\gamma, we find evidences of gradients in the age of HII regions along the ring of Mrk 42, favoring the pearls on a string scenario of star formation. The broad component of Paβ\beta emission line presents a Full Width at Half Maximum (FWHM) of ∼\sim1480 kms−1^{-1}, implying in a mass of ∼ 2.5×106\sim\,2.5\times10^{6}~M⊙_{\odot} for the central supermassive black hole. Based on emission-line ratios we conclude that besides the active galactic nucleus, Mrk 42 presents nuclear Starburst activity.Comment: 14 pages, MNRAS accepte

    AGN feedback and star formation in the peculiar galaxy NGC 232: Insights from VLT-MUSE Observations

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    We use VLT-MUSE integral field unit data to study the ionized gas physical properties and kinematics as well as the stellar populations of the Seyfert 2 galaxy NGC\,232 as an opportunity to understand the role of AGN feedback on star formation. The data cover a field of view of 60×\times60 arcsec2^{2} at a spatial resolution of ∼\sim\,850\,pc. The emission-line profiles have been fitted with two Gaussian components, one associated to the emission of the gas in the disc and the other due to a bi-conical outflow. The spectral synthesis suggests a predominantly old stellar population with ages exceeding 2\,Gyr, with the largest contributions seen at the nucleus and decreasing outwards. Meanwhile, the young and intermediate age stellar populations exhibit a positive gradient with increasing radius and a circum-nuclear star forming ring with radius of ∼\sim0.5\,kpc traced by stars younger than 20 Myr, is observed. This, along with the fact that AGN and SF dominated regions present similar gaseous oxygen abundances, suggests a shared reservoir feeding both star formation and the AGN. We have estimated a maximum outflow rate in ionized gas of ∼\sim1.26\,M⊙{\odot}\,yr−1^{-1} observed at a distance of ∼\sim560 pc from the nucleus. The corresponding maximum kinetic power of the outflow is ∼3.4×1041\sim3.4\times10^{41} erg\,s−1^{-1}. This released energy could be sufficient to suppress star formation within the ionization cone, as evidenced by the lower star formation rates observed in this region.Comment: 14 pages,10 figures. Submitted to MNRA

    Spatially resolved observations of outflows in the radio loud AGN of UGC 8782

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    We use optical Integral Field Spectroscopy (IFU) to study the gas emission structure and kinematics in the inner 3.4×\times4.9 kpc2^2 region of the galaxy UGC 8782 (3C 293), host of a radio loud Active Galactic Nucleus (AGN). The observations were performed with the GMOS-IFU on the Gemini North telescope, resulting in a spatial resolution of ∼725\sim725 pc at the distance of the galaxy. While the stars present ordered rotation following the orientation of the large scale disc, the gas shows a disturbed kinematics. The emission-line profiles present two kinematic components: a narrow (σ≲200\sigma\lesssim200 km s−1^{-1}) component associated with the gas in the disc of the galaxy and a broad (σ≳200\sigma\gtrsim200 km s−1^{-1}) component produced by gas outflows. Emission-line ratio diagrams indicate that the gas in the disc is excited by the AGN radiation field, while the emission of the outflow includes additional contribution of shock excitation due to the interaction of the radio jet with the environment gas. Deviations from pure rotation, of up to 30 km s−1^{-1}, are observed in the disc component and likely produced by a previous merger event. The broad component is blueshifted by ∼150−500\sim150-500 km s−1^{-1} relative to the systemic velocity of the galaxy in all locations. We construct radial profiles of the mass outflow rate and kinetic power of the ionized gas outflows, which have the maximum values at ∼1\sim1 kpc from the nucleus with peak values of M˙out,ΔR=0.5±0.1\dot{M}_{\rm out,\Delta R}=0.5\pm0.1 M⊙_\odot yr−1^{-1} and K˙out,ΔR=\dot{K}_{\rm out,\Delta R} =(6.8±\pm1.1)×\times1041^{41} erg s−1^{-1}. The kinetic coupling efficiency of these outflows is in the range of 1−-3 per cent, indicating that they could be powerful enough to affect the star formation in the host galaxy as predicted by theoretical simulations.Comment: Accepted for publication by MNRA

    SDSS-IV MaNGA: Identification of active galactic nuclei in optical integral field unit surveys

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    In this paper, we investigate 2727 galaxies observed by MaNGA as of June 2016 to develop spatially resolved techniques for identifying signatures of active galactic nuclei (AGN). We identify 303 AGN candidates. The additional spatial dimension imposes challenges in identifying AGN due to contamination from diffuse ionized gas, extra-planar gas and photoionization by hot stars. We show that the combination of spatially-resolved line diagnostic diagrams and additional cuts on Hα\alpha surface brighness and Hα\alpha equivalent width can distinguish between AGN-like signatures and high-metallicity galaxies with LINER-like spectra. Low mass galaxies with high specific star formation rates are particularly difficult to diagnose and routinely show diagnostic line ratios outside of the standard star-formation locus. We develop a new diagnostic -- the distance from the standard diagnostic line in the line-ratios space -- to evaluate the significance of the deviation from the star-formation locus. We find 173 galaxies that would not have been selected as AGN candidates based on single-fibre spectral measurements but exhibit photoionization signatures suggestive of AGN activity in the MaNGA resolved observations, underscoring the power of large integral field unit (IFU) surveys. A complete census of these new AGN candidates is necessary to understand their nature and probe the complex co-evolution of supermassive black holes and their hosts.Comment: 18 pages, 11 figures, accepted to MNRA
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